"People don't stop killers. People with guns do."

Virginia Tech doesn’t have that kind of trust in its students (or its faculty, for that matter) [to carry weapons responsibly]. Neither does the University of Tennessee. Both think that by making their campuses “gun-free,” they’ll make people safer, when in fact they’re only disarming the people who follow rules, law-abiding people who are no danger at all.

This merely ensures that the murderers have a free hand. If there were more responsible, armed people on campuses, mass murder would be harder.

In fact, some mass shootings have been stopped by armed citizens. Though press accounts downplayed it, the 2002 shooting at Appalachian Law School was stopped when a student retrieved a gun from his car and confronted the shooter. Likewise, Pearl, Miss., school shooter Luke Woodham was stopped when the school’s vice principal took a .45 from his truck and ran to the scene. In February’s Utah mall shooting, it was an off-duty police officer who happened to be on the scene and carrying a gun.

Police can’t be everywhere, and as incidents from Columbine to Virginia Tech demonstrate, by the time they show up at a mass shooting, it’s usually too late. On the other hand, one group of people is, by definition, always on the scene: the victims. Only if they’re armed, they may wind up not being victims at all.

“Gun-free zones” are premised on a fantasy: That murderers will follow rules, and that people like my student, or Bradford Wiles, are a greater danger to those around them than crazed killers like Cho Seung-hui. That’s an insult. Sometimes, it’s a deadly one.

The only thing I'd say is that there are actually two competing considerations:

1) How many murders will be stopped due to widespread gun carrying?

2) How many additional murders will be caused by widespread gun carrying?

The fact of the matter is -- and I doubt that Reynolds would disagree with so irrefutable a point -- is that an argument, a bar fight, some frat guys getting into a fight with a rival frat -- can escalate from rowdy to deadly if a gun is involved. Most people aren't good enough at fighting to kill or even permanantly wound an opponent with their fists and feet. The chance of serious injury is always there, but it's a relatively low chance.

On the other hand, there's always the chance that a guy on the wrong end of a beating -- not a mugging or wildpacking or other case of sudden savage violence; just a guy who got into a fight, willingly, and now is finding maybe that wasn't such a great idea -- might pull out his gun and might start shooting.

And the chance of him killing or permanently wounding his opponent are rather high.

The thing is that while massacres like the one at VaTech are heartbreaking, they're also incredibly rare. The fight-that-turns-deadly situation is much more common.

So whether or not gun-free zones are a good idea turns on simple numbers. Ignoring the constitutional, rights-based arguments, as I often do (as someone tends to believe the constitution dictates whatever they consider good public policy; it's rare that someone argues the Constitution demands a policy they personally disagree with) -- which policy will actually lead to more deaths?

Obviously, if a liberal carry policy results in stopping the slaughter of 20 but also results in 50 extra deaths next year... well, I'm not a mathematician, but that doesn't seem to me to be a gain.